Interactions of cosmological gravitational waves and magnetic fields

Elisa Fenu; Ruth Durrer

doi:10.1103/physrevd.79.024021

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arXiv · 0809.1383

Interactions of cosmological gravitational waves and magnetic fields

Elisa Fenu·Ruth Durrer

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Abstract

The energy momentum tensor of a magnetic field always contains a spin-2 component in its anisotropic stress and therefore generates gravitational waves. It has been argued in the literature (Caprini & Durrer \cite{CD}) that this gravitational wave production can be very strong and that back-reaction cannot be neglected. On the other hand, a gravitational wave background does affect the evolution of magnetic fields. It has also been argued (Tsagas et al. \cite{Tsagas:2001ak},\cite{Tsagas:2005ki}) that this can lead to very strong amplification of a primordial magnetic field. In this paper we revisit these claims and study back reaction to second order.

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Elisa Fenu, Ruth Durrer. 2009-01-05. Interactions of cosmological gravitational waves and magnetic fields. https://doi.org/10.1103/physrevd.79.024021

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